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Re: Seizures

In a message dated 96-09-28 09:50:09 EDT, 

Shef sez,
<< << trunk. It is good that I have this strange practice, because after I'd
  "never-seized" and finger tighten all the plugs, then carefully torqued
  into place I found that my stock Audi plug wires wouldn't fit over them.
  I'd reme >>

Then Scott replies,
 I hope that your reference to "never seize"  is not anti seize compound....
  Don't use it, it is not necessary....  A good thread cleaning is better,
 a chaser thru it if you have concerns...  Otherwise you run the risk of
 backing out over time, since you are threading steel into aluminum, and they
 have different heat expansion rates, the only thing that "keeps" them
 over time is the crud that forms on the threads...-- snippage> --
 You don't need it there, and from a lucky (and forewarned by yours
 truly) Waterford participant, don't put it on the wheel lugs either.....
 Scott >>

I agree with Scott.  The majority of torque specifications are "dry torque"
values, (mating surfaces clean and dry).  If the specification requires a
lubricant they should be specified in the torque tables for that particular
fastner.  By adding a lubricant (anti-sieze is one) you essentially reduce
the friction of the mating parts and cause the fastener to "stretch" a bit
more before desired torque is reached.  This extra stretch equates to undo
stress and eventually fatigue of the fastener, especially when cyclic heat is
involved.  In other words you will end up over-torqueing the fastener.  While
most fasteners have a large of forgiveness factor, others are torque
critical!!!  Aluminum is one of the less forgiving...

Bruce Johnson
85 4Ksq
Olympia, WA